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Modification of Doses of Efavirenz According to Its Blood Concentration in HIV Patients

This study has been completed.
Information provided by (Responsible Party):
Dr . BONAVENTURA CLOTET, Germans Trias i Pujol Hospital Identifier:
First received: March 3, 2006
Last updated: September 15, 2016
Last verified: October 2008
This is a study on the utility of the modification of doses of efavirenz guided by its plasma concentration (therapeutic drug monitoring) in HIV-infected patients initiating treatment with Sustiva.

Condition Intervention Phase
Drug: Efavirenz capsules 200 mg and 600 mg
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Open, Parallel and Randomised Pilot Clinical Trial to Evaluate the Utility of the Therapeutic Monitoring of Plasma Levels of Efavirenz in Hiv-Infected Patients Initiating an Antiretroviral Treatment Regimen With Sustiva

Resource links provided by NLM:

Further study details as provided by Germans Trias i Pujol Hospital:

Primary Outcome Measures:
  • The proportion of patients who need to interrupt treatment with efavirenz due to virological failure [ Time Frame: after 96 weeks of follow-up ]

Secondary Outcome Measures:
  • The proportion of patients who need to interrupt treatment with efavirenz due to adverse side effects [ Time Frame: after 96 weeks of follow-up ]
  • To determine the incidence of adverse events and the toxicity profile (haemogram, AST/ALT/FA/GGT, creatinine, urea) [ Time Frame: during the 96 weeks of follow-up ]
  • To evaluate the proportion of patients with plasma levels of efavirenz between 1.0 and 4.0 mg/L [ Time Frame: during the 96 weeks of follow-up ]
  • To evaluate the relationship between the appearance of secondary events during treatment with efavirenz and the patients' demographic and clinical characteristics, as well the plasma concentration of efavirenz [ Time Frame: during the 96 weeks of follow-up ]
  • To evaluate the variations in CD4 and CD8 lymphocyte count [ Time Frame: during the 96 weeks of follow-up ]

Enrollment: 31
Study Start Date: September 2006
Study Completion Date: October 2008
Primary Completion Date: October 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
No Intervention: Control
Efavirenz capsules 600 mg
Experimental: Experimental
Modification of doses of efavirenz guided by its plasma concentration (therapeutic drug monitoring)
Drug: Efavirenz capsules 200 mg and 600 mg
Modification of doses of efavirenz guided by its plasma concentration (therapeutic drug monitoring)
Other Name: Sustiva

Detailed Description:

Currently, efavirenz is dosed systematically, without taking into account the individual characteristics of each individual patient. However, plasma concentration of efavirenz may widely vary between different subjects that receive the same dose of the drug (interindividual variability).

Therapeutic drug monitoring (TDM) signifies individualised pharmacological dosing, based on the plasma levels that each patient presents. This strategy has been broadly used in the field of the treatment of other medical conditions and is acquiring growing interest in the field of antiretroviral treatment. Thus, the use of TDM for the treatment of naïve patients with nelfinavir or with indinavir has translated into an increase in the proportion of individuals with suppressed viral load and also into a reduction in HAART-induced adverse events . However, data on the utility of the therapeutic monitoring of the levels of efavirenz in HIV-infected patients are very scant.

On the basis of the above, it might be thought that the modification of the doses of efavirenz, guided by its plasma concentration, in patients receiving this drug and whose plasma levels of efavirenz are outside the therapeutic range, might improve the tolerability of the treatment without compromising virological efficacy.


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • HIV-1 patients.
  • According to the criteria of the treating physician, the need to initiate a regimen of antiretroviral treatment that includes efavirenz (both antiretroviral-naive patients and others on treatment with protease inhibitors switching to efavirenz for salvage reasons or for simplification of the anti-retroviral therapy are included).
  • Absence of opportunistic infections and/or tumours in the three months prior to inclusion.

Exclusion Criteria:

  • History of allergic hypersensitivity to the investigational drug.
  • History of previous failure with antiretroviral treatment with non-nucleoside reverse transcriptase inhibitors or previously documented resistance to efavirenz
  • History of psychiatric comorbidity which, in the investigator's opinion, renders the use of efavirenz inadvisable.
  • Active consumption of alcohol (>50 g/day) or other illegal drugs (except cannabis)
  • Suspicion of unsuitable compliance with the antiretroviral treatment.
  • Pregnant women or breast-feeding mothers.
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Please refer to this study by its identifier: NCT00299091

Germans Trias i Pujol Hospital
Badalona, Barcelona, Spain, 08916
Sponsors and Collaborators
Principal Investigator: Bonaventura Clotet, MD, PhD Lluita Sida Foundation-HIV Unit
  More Information

Responsible Party: Dr . BONAVENTURA CLOTET, Dr. Bonaventura Clotet, Germans Trias i Pujol Hospital Identifier: NCT00299091     History of Changes
Other Study ID Numbers: startTDM-EFV
Study First Received: March 3, 2006
Last Updated: September 15, 2016

Keywords provided by Germans Trias i Pujol Hospital:
Therapeutic drug monitoring
Treatment Naive
Treatment Experienced

Additional relevant MeSH terms:
Reverse Transcriptase Inhibitors
Nucleic Acid Synthesis Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Anti-Retroviral Agents
Antiviral Agents
Anti-Infective Agents
Cytochrome P-450 CYP2C9 Inhibitors
Cytochrome P-450 Enzyme Inhibitors
Cytochrome P-450 CYP2C19 Inhibitors
Cytochrome P-450 CYP2B6 Inducers
Cytochrome P-450 Enzyme Inducers
Cytochrome P-450 CYP3A Inducers processed this record on May 22, 2017